In an imaging sensor such as a CMOS image sensor, a signal obtained from a light receiving pixel may include noise due to a dark current, so that the black level of the signal of the light receiving pixel is deviated from an ideal level. When the black level of the signal of the light receiving pixel is deviated from the ideal level, white floating or black sinking may be generated in a picture corresponding to signals of a plurality of light receiving pixels. Therefore, it is desired to correct the black level of the signal of the light receiving pixel with high accuracy.